Pneumatic action for pianos.



No. 821,917. PATBNTED MAY 29, 190e.

A. ANDERSON. A PNEUMATIG ACTION POR PIANos.

AIPLIOATION FILED AUG. 24, 1904.

3 SHEETS-SHEET 1.

. a@ mw neere f PATENTED MAY 29, 1906.

A. ANDERSON, PNEUMATIG ACTION. FOR-PIANS.

APPLICATION FILED AUG. 24, 1904.

3 SHEETS-SHEET 2,

PATENTED MAY 29, 1906.-

3 SHEETS-SHEET s.

A. ANDERSON. PNEUMATIG ACTION PON PIANos. APPLICATION FILED AUG. 24, 1 904.

. Unir-nn srarns Parana ,clarion g ALFRED ANDERSON, or cercado; ILLiNoi'sl sussidiarie Ac'rlo'm sometimes.

Specicaton of Letters Patent.

Patented may 29, 1906.

Application filed August 24, 1904. Serial No. 221.941.

To all whont it may concern.-

13e it known that I, ALFRED ANDERSON, a. citizen of the United States, residing at Chicago, in the county of Cook and State ofllli. nois, have invented certain-new and useful' Improvements in Pneumatic Actions for Pianos, of whiclrthe following is a specification.

This invention relates to improvements in that class of pneumatic actions used in what is known to the trade as pianclas; and it consists in certain novel features of. the construction,combination, and arrangement of the several parts of the improved action whereby important advantages are attained and the deviceis made simpler, cheaper, and otherwise better adapted and more conven ient'for use, all as will be hereinafter fully set forth and specifically claimed.

ln order to enable others'skilled in the art towhichmy invention pertains to make and use the same, will now proceed to describe fit, referring to the accompanying drawings, in which- FigureY 1 is a cross-sectional view of a pneumatic action embodying my invention, showl ing a portion of a piano and illustrating the improved action in position for operating the keys of the piano. Fig. 2 isafront view, partly ix section and partly in elevation, of the action, showing the casing therefor brokenv away to illustrate the operating mechanism. FigJ 3 is va plan view of like parts as shown in Fig. ,2. Fig. 4 is a fragmental face view of the valve-seat board. Fig. 5 is a perspective view of a portion of the frame which carries the brackets which support the valve-stems; and Fig. 6 is a detail view of one ,of the valves, showing it detached.

Likenumerals of reference refer to corresp onding parts throughout the different views -of the drawings.

The reference-numeral 10 represents the casing, which may be of any suitable size, form, and material, but preferably rectangular in shape, and is provided at its top with a hinged door 11, which may be raised so as to permit of the insertion of the roller 12, on

which the perforated music-sheet 13 is wound. This roller vis adapted to be journaled longitudinally in the upperportion of thecasing on 'one side of the tracker board or bar 14, and the sheet 13 is ada ted to be woundon a roller 15, mounted an driven in any welleknown manner on the opposite side by means of pieces 16 and 17, one of which is tudinal opening 19, through which the str1 of the tracker-board, which is preferably supported in an inclined position, as shown,

secured at one of its edges tothe u per p0rvtion of the casing and at its othere ge to the surface ofV the board 14, adjacent to the pi` ano 18, while the other .one is secured at one yofits edges on the inner surface of the casing and at its other edge to the rear surface of the tracker-board. That side of the casing 10 ad'acent to the piano 18, and which portion: will hereinafter be referredfto as the front part of the device, is provided with a longingdevers, which actuate the keys20 and 21 of the piano, project. Horizontally mount-v ed on the inner surface of the front art of the casing 10, just below the horizonte opening 19 therein, is a primary or pneumatic a seriesof seats 23 and 24, each of which is covered by means of a pouch or diaphragm 25, of leather or other suitable flexible material. The recesses or seats 23 are arranged in a row longitudinally above the recesses or seats 24, which-are also arranged .ina longitudinal row; butsaid recesses 23 and 24 are located out of vertical alinement with onev another, as will be 'readilyy understood by .ref-

-erence to Figs; 1l and 2 of the drawings. V

Leading from each of the recesses or seats Y 23 and 24 to the top ofthe board 22 is a chanv nel 26, in the upper end of each of which is fitted a tube 27 to the upper end of each of which a reed or ipe 28 isconnected vat one of its "ends, the otlli) cate with channels 29, which extend ,through the uppersurface of the tracker-board. In order to prevent weakening ofl this board-, these channels 29 may beqnade out of alinement with one another, as shown in Fig. 1 of the drawings.

Secured to the inner orrear surface ofthe IOC board 22 is a valve-supporting frame 30, which is incross-section in the forri of three sides of a rectangular figure, having its side adjacent to the hoard 22 open. The upper portion of the valve-supporting frame 30is1A provided with a longitudinal channel 31,v which communicateswith each of the chan--` nels 2G in the primary board through kports 32, which are coated justbelow the lower ends of the tubes`27, as is clearly shownin Figs. 1, 2,- and 5 of the drawings. The rear "ortion of vthe frame 30 is provided Withtwo ongitudinal' rowsjof openings 33 and 34,

er ends of which communiwhich are arranged out ot" vertical alinement with one another and so that the openings ID3 and 34willievister, respectively, with therecesses or seats 23 and 24 in the primary board. rPhe channel 31 has communication through the openings 35 with the cavity of the 'trame 30, so that the air may be exil .ustcd therefrom through the pipe 36, which communicates with the main or operating bellows, (Not shown.) Y

Located in inclined positions on the inner surface of the frame 30er-e a series of brackets 37, employed to support the valve-stems 3S, each of which has on one of its ends a button 39, to rest against the inner surfaces of' the pouches of the primary board. Each of the valve-stems 38 has mounted on its rear portion a valve 40, which is held looosely between two collars 41 on the stem, which collars have their pcripheries provided with telt to prevent rattling.

As shown in Figs. 1 and 5 of the drawings, the brackets 37 are provided with prongs 42 at each ot their ends, which prongs have openings 43 to receive the valve-stems. It will also be apparent by reference to said figures that the openings in the upper ends of the brackets 37 will register with the openings 33 in the 'frame 3() and with the recesses 23, in the board 22, while the openings 4?) in the lower ends of the brackets will register with the openings .9i-'l in ille board 23() and the recesses 24 in. the primary hoard Lof-ated on the rear surface oln the valve-sumiortiug lramc is the main. valve-bmnd l-l, which has on its front surl'ace, or that surl'aee thereoi'A adjacent to the 'l'raine 30, a series of openinqs45 and 16, arranged in longitudinal parallel rows` but out of vertical alinenient with each other. ln each el the openings -l-(i and 45 are tubular portions 4S and L1l), respectively, which have their free ends protected by means ol" l'el1 or leather rings Jiflagainst which the 'valves l() ill'iinl'iinge. The. rear sinl'ace ol' the hoard -l-l is l'orined just above each ol the openings 115, with an opening 5i), which coininuneaLes with the openings 45, as lshown in Figs. i and 4 ot' the drawings.

Below each ol' the openings` 46 in the board 4() and on the r yar surface .hercol is an Opening 51 each olE which communicates with the openings i6 as will he readily understood by relere e to the last-named ligures. Mounted longitin'linall)v on the 'upper surfaces ot the boards 30 and 44, so as to cover the channel 31 in the board 30, is a supporting-strip 52, which has a series otupwardlyextending projections 53, through which is passed a rod 54, on which the. striking-levers 55 and 56 are liulcrumed. `Each of these levers has at its forward end a downward extension 57, which may be cushioned so as to strikctlie keys 2() and 21 of the piano softly. Horizontally located at the rear oi the board 4') are twoshclves 58 and 59, which support a eener? series of bellows 60 and 61, respectively. The bellows-shelf 58 has extending from its front edge rearwardly a series oi'A channels 62, which register and communicate with the openings in the rear surface ol the board 44, and the shelf 59 has extending from its front edge a series of channels 63, which register and communicate with the openings 51 in the lower portion of the board 44, as is shown by dotted lines in Fig. l of the drawings. The rear ends of the channels 62 and 63 communicate with a '"series of bellows 6() and 61, respectively, which are secured to the lower surfaces of said shelves. Each ot' these bellows is provided at its front end with an cXpai'iding-spring 64, employed to assist in inl'lating or expanding the bellows. The rear end ot cach of the bellows is provided with a projection 65, to which is adjustably secured an upwardly-extending rod 66, which is adjustably secured at its other ends to the rear ends of the striking-levers and 56, as shown in Fig. 1 of the drawings.

From the foregoing and by reference to the drawings it will be seen and clearly understood that by exhausting air through the conduit or pipe 36 equal tension or pressure will be exerted on both sides of the pouches 25. but when atmospheric air is admitted th yugh the tracker-board it will pass thy )ugh the channels 29, pipes 28, and tubes 27 and immediately inflate the pouches 25, and thereby open the valves of the ports33 and 34, thus putting the bellows and 6l in communication with the exhaust, whereby they will be deflated. to operate the Ilevers 55 and 56, thus causing them to actuate the keys of the piano.

Having thus fully described my invention, what l claim as new, and desire to secure by Letters Patent, is-- In a pneumatic action for pianos, the combination with the casing, of a series ot keyactuating levers lulcrumed therein, a trackerho'ard mounted near said levers and having a series of channels, a primary board located in the trout part of the casing and having a series ot' recesses provided with channels having communication with the channels ot the tracker-board, a diaphragm mounted over each of said recesses, a hollow supportingboard lor the valves located on the inner surleee of the primary board and having a series of openings registering with the diaphragm-recesses, the cavity of said valvesui'iporting board having communication with each of the channels leading from the daphragni-rcccsses, a series of valve-supporting brackets cach having its ends bifurca ted and provided with apertures, said brackets being secured in an inclined position on the inner surface of the rear portion of said supporting-board, a main valve-seat board located on the rear surface of said supportingboard and having a series of openings each provided with si tubular.valve-seat therein,A

said main board having in its reel' surface a, series of openin s communicating with the openings'in the ont surfalee thereof, `the tubuler valve-seats and the openings in the front surface of the main board re isterng with the openings in the supportingoard, a

-seres of Avalves movably mounted on the brackets o-the supporting-board to open end close the o enin s therein as Well as to'open end close t e -tu ular valve-seats, the stems of said valves adapted `to* impinge et one of their ends` the diaphragme', a Series of-beH-ows having communication With `the openings on -the rear surface of said main board, adjustable Connections uniting the rear ends of the striking-leversto the belowsendmeans to supply air 13o the cavity of the supporting- .board, substentelly es describedu 

